src/basic/process-util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2010 Lennart Poettering
   8
   9   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <alloca.h>
  24 #include <sched.h>
  25 #include <signal.h>
  26 #include <stdbool.h>
  27 #include <stddef.h>
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <sys/resource.h>
  31 #include <sys/types.h>
  32
  33 #include "format-util.h"
  34 #include "ioprio.h"
  35 #include "macro.h"
  36 #include "time-util.h"
  37
  38 #define procfs_file_alloca(pid, field)                                  \
  39         ({                                                              \
  40                 pid_t _pid_ = (pid);                                    \
  41                 const char *_r_;                                        \
  42                 if (_pid_ == 0) {                                       \
  43                         _r_ = ("/proc/self/" field);                    \
  44                 } else {                                                \
  45                         _r_ = alloca(STRLEN("/proc/") + DECIMAL_STR_MAX(pid_t) + 1 + sizeof(field)); \
  46                         sprintf((char*) _r_, "/proc/"PID_FMT"/" field, _pid_);                       \
  47                 }                                                       \
  48                 _r_;                                                    \
  49         })
  50
  51 int get_process_state(pid_t pid);
  52 int get_process_comm(pid_t pid, char **name);
  53 int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line);
  54 int get_process_exe(pid_t pid, char **name);
  55 int get_process_uid(pid_t pid, uid_t *uid);
  56 int get_process_gid(pid_t pid, gid_t *gid);
  57 int get_process_capeff(pid_t pid, char **capeff);
  58 int get_process_cwd(pid_t pid, char **cwd);
  59 int get_process_root(pid_t pid, char **root);
  60 int get_process_environ(pid_t pid, char **environ);
  61 int get_process_ppid(pid_t pid, pid_t *ppid);
  62
  63 int wait_for_terminate(pid_t pid, siginfo_t *status);
  64
  65 typedef enum WaitFlags {
  66         WAIT_LOG_ABNORMAL             = 1U << 0,
  67         WAIT_LOG_NON_ZERO_EXIT_STATUS = 1U << 1,
  68
  69         /* A shortcut for requesting the most complete logging */
  70         WAIT_LOG = WAIT_LOG_ABNORMAL|WAIT_LOG_NON_ZERO_EXIT_STATUS,
  71 } WaitFlags;
  72
  73 int wait_for_terminate_and_check(const char *name, pid_t pid, WaitFlags flags);
  74 int wait_for_terminate_with_timeout(pid_t pid, usec_t timeout);
  75
  76 void sigkill_wait(pid_t pid);
  77 void sigkill_waitp(pid_t *pid);
  78
  79 int kill_and_sigcont(pid_t pid, int sig);
  80
  81 int rename_process(const char name[]);
  82 int is_kernel_thread(pid_t pid);
  83
  84 int getenv_for_pid(pid_t pid, const char *field, char **_value);
  85
  86 bool pid_is_alive(pid_t pid);
  87 bool pid_is_unwaited(pid_t pid);
  88 int pid_from_same_root_fs(pid_t pid);
  89
  90 bool is_main_thread(void);
  91
  92 noreturn void freeze(void);
  93
  94 bool oom_score_adjust_is_valid(int oa);
  95
  96 #ifndef PERSONALITY_INVALID
  97 /* personality(7) documents that 0xffffffffUL is used for querying the
  98  * current personality, hence let's use that here as error
  99  * indicator. */
 100 #define PERSONALITY_INVALID 0xffffffffLU
 101 #endif
 102
 103 unsigned long personality_from_string(const char *p);
 104 const char *personality_to_string(unsigned long);
 105
 106 int safe_personality(unsigned long p);
 107 int opinionated_personality(unsigned long *ret);
 108
 109 int ioprio_class_to_string_alloc(int i, char **s);
 110 int ioprio_class_from_string(const char *s);
 111
 112 const char *sigchld_code_to_string(int i) _const_;
 113 int sigchld_code_from_string(const char *s) _pure_;
 114
 115 int sched_policy_to_string_alloc(int i, char **s);
 116 int sched_policy_from_string(const char *s);
 117
 118 #define PTR_TO_PID(p) ((pid_t) ((uintptr_t) p))
 119 #define PID_TO_PTR(p) ((void*) ((uintptr_t) p))
 120
 121 void valgrind_summary_hack(void);
 122
 123 int pid_compare_func(const void *a, const void *b);
 124
 125 static inline bool nice_is_valid(int n) {
 126         return n >= PRIO_MIN && n < PRIO_MAX;
 127 }
 128
 129 static inline bool sched_policy_is_valid(int i) {
 130         return IN_SET(i, SCHED_OTHER, SCHED_BATCH, SCHED_IDLE, SCHED_FIFO, SCHED_RR);
 131 }
 132
 133 static inline bool sched_priority_is_valid(int i) {
 134         return i >= 0 && i <= sched_get_priority_max(SCHED_RR);
 135 }
 136
 137 static inline bool ioprio_class_is_valid(int i) {
 138         return IN_SET(i, IOPRIO_CLASS_NONE, IOPRIO_CLASS_RT, IOPRIO_CLASS_BE, IOPRIO_CLASS_IDLE);
 139 }
 140
 141 static inline bool ioprio_priority_is_valid(int i) {
 142         return i >= 0 && i < IOPRIO_BE_NR;
 143 }
 144
 145 static inline bool pid_is_valid(pid_t p) {
 146         return p > 0;
 147 }
 148
 149 static inline int sched_policy_to_string_alloc_with_check(int n, char **s) {
 150         if (!sched_policy_is_valid(n))
 151                 return -EINVAL;
 152
 153         return sched_policy_to_string_alloc(n, s);
 154 }
 155
 156 int ioprio_parse_priority(const char *s, int *ret);
 157
 158 pid_t getpid_cached(void);
 159 void reset_cached_pid(void);
 160
 161 int must_be_root(void);
 162
 163 typedef enum ForkFlags {
 164         FORK_RESET_SIGNALS = 1U << 0,
 165         FORK_CLOSE_ALL_FDS = 1U << 1,
 166         FORK_DEATHSIG      = 1U << 2,
 167         FORK_NULL_STDIO    = 1U << 3,
 168         FORK_REOPEN_LOG    = 1U << 4,
 169         FORK_LOG           = 1U << 5,
 170 } ForkFlags;
 171
 172 int safe_fork_full(const char *name, const int except_fds[], size_t n_except_fds, ForkFlags flags, pid_t *ret_pid);
 173
 174 static inline int safe_fork(const char *name, ForkFlags flags, pid_t *ret_pid) {
 175         return safe_fork_full(name, NULL, 0, flags, ret_pid);
 176 }
 177
 178 int fork_agent(const char *name, const int except[], unsigned n_except, pid_t *pid, const char *path, ...);